Method for producing sterilized elements from fibrous material and an article produced therefrom



Oct. 3, 1967 H. MICHELS METHOD FOR PRODUCING STERILIZED ELEMENTS FROM FIBROUS MATERIAL AND AN ARTICLE PRODUCED THEREFROM Filed April 1, 1964 1 INVENTOR Herm n/z Mic Eel ATTVS.

United States Patent 3,344,784 METHOD FOR PRODUCING STERILIZED ELE- MENTS FROM FERGUS MATERIAL AND AN ARTICLE PRGDUCED THEREFRGM Hermann Michels, Rauschendorf, near Siegburg, Germany, assignor to Ypsilon-W-erk Wienke & Miehels K.G., Troisdorf, Germany Filed Apr. 1, 1964, Ser. No. 356,537 Claims priorit applicatiogaGermany, Apr. 4, H63, Y ,4 6 Claims. ((31. 128-156) This invention relates to a novel method of and apparatus for the production of diversely shaped sterilized elements of fibrous material, and in particular, to the production of pressed articles such as surgical dressings made of fibrous material, e.g. gauze, cotton wool, cotton wool gauze, compresses, cellulose gauze compresses, fibre fleece compresses arid the like.

It is well known that dressings, packets or elements produced from fibrous material generally occupy a considerable amount of space, are relatively bulky, and are therefore difiicult to store and transport in large quantities as well as expensive to transport. To reduce both storage and transport costs it has been proposed to subject such fibrous material elements to a pressing operation during the production thereof in order that the fibrous material is compressed into the smallest possible size. Achieving the smallest size fibrous material element is desirable not only to reduce storage and transportation costs, but to increase the quantity of such elements that can be stored in low-volume emergency kits, such as First Aid Kits.

After the termination of the conventional pressing operation, fibrous material elements are generally sterilized,

cooled and thereafter wrapped. These steps take place or in the case of relatively small packets, a plurality of individual packets are assembled to form a relatively larger pack, and the entire pack is subjected to the pressure of a press. The press generally includes one or more die cavities contoured to a particular configuration, and during the pressing operation, the pack or packets are conformed to the configuration of the die cavities.

The pressed pack or packets are then removed from the press and are tied so that the particular configuration imparted thereto by the die cavities is retained with as little change in external dimensions of the packs or packets as is possible. However, most of the fibrous material used to form such packs, packets or elements is of an elastic nature and tends to extend or rebound to its originally generally bulky unconfined state when removed from the press.

The tied or bound elements are then sterilized by storing the same loosely in containers or baskets in a sterilization chamber which is appropriately heated. After the sterilization operation the elements remain tied and are not untied until the same are to be opened for use.

Tied packs or elements produced in accordance with the above have numerous inherent disadvantages. For example, it has been found that the'elastic nature of the fibrous material bulges the material outwardly from the pack adjacent the tying means to form a relatively irregularly shaped element. Without tying, of course, the element would not retain the configuration to which it was pressed during the pressing operation. When such tied elements have been opened by releasing conventional tying means, the fibrous material is no longer restrained and rebounds unin-hibitedly to return the fibrous material to an almost formless shape corresponding to its shape prior to being hand compressed.

This tendency of the fibrous material to rebound indiscriminately in all directions and to thus increase in volume also increases the possibility of the element becoming unsterilized since the larger volume of the fibrous material affords easier access for bacteriological contamination than a smaller mass of uniformly compacted material.

In addition to these disadvantages it has heretofore been virtually impossible to avoid pressing the tied packs to a configuration which does not exactly facilitate the storage and stacking thereof. This is primarily due to the lateral bulging of the conventional tying means which results in the familiar shape which corresponds very roughly to a prismatic configuration. This outward bulging requires more room for a stack of such elements or packs than would he obviously required for precisely rectangularly shaped packs, or other configurations which were generally flat-sided.

Another disadvantage in the conventional formation of such packs is the tendency of the wrapping sheet or covering itself to become infolded with the fibrous material during the pressing operation. In most cases, the Wrapping sheet is merely a paper envelope into which the fibrous material is stuffed, and this envelope cannot be reduced in volume during the reduction in volume of the fibrous material during the pressing operation. Thus, the envelope conforms itself to the general configuration of the die cavity by being infolded or merged with the fibrous material, and generally deformed into a plurality of folds during the conventional pressing operation. The result is an assem ly of individual packets which are varied in cross-sectional configuration and are generally completely non-uniform, with crescent-shaped cross-sections predominating.

From the foregoing it is believed readily apparent that conventional processes heretofore employed for the production of packets or packs of fibrous material particularly adapted for dressing purposes have numerous inherent disadvantages precluding the production of such packets which can be controlled in shape, cross-section and volume, and which are therefore extremely difiicult to stack, are uneconomical to produce because of the time and material required to perform the mentioned tying operation, and are also more likely to become unsterile because of their tendency to rebound and increase in volume after the tying means are released.

It is therefore, an object of this invention, to provide a novel method which substantially eliminates each of the above inherent disadvantages in prior art processes, and is particularly characterized as follows:

In accordance with this invention an element or packet or a plurality of such packets are shaped by a pressing operation similar to that heretofore described. However, in lieu of the immediate release of the conventional pressing pressure the packets are held under a clamping pressure which maintains the particular shape or configuration imparted to the packets by the press. While the packets are still subjected to the clamping pressure they are sterilized and cooled, and the clamping pressure is removed only after the packets have cooled sufliciently to retain their pressed shape (preferably room temperature).

By following this method dressing packets are obtained which are composed of predetermined quantity of fibrous material, and which retain the particular shape or configuration imparted thereto 'by the clamping pressure. This is substantially due to the fact that the dressing packets are retained in their particular pressed configuration by the clamping pressure which is not removed until the packets have cooled, thus substantially eliminating the rebound tendency of the generally elastic fibrous material of the packets.

The clamping pressure is suflicient to prevent the shaped or pressed packets from losing their pressed form, and prevent the usual tendency of the packets to swell up during the sterilizing operation. Accordingly, in practicing the invention it is possible to form packets having surfaces or walls which are substantially absolutely plain surfaces, such as parallelepipeds or similar prismatic forms. Any other shape, could be imparted to the packets depending upon the particular configuration of the die cavities, but irrespective of the configuration of the packets, the form imparted thereto will be retained without conventional tying means heretofore employed in the prior art. Fibrous material packets constructed in accordance with the novel method of this invention not only achieve extremely efllcient stacking, by the absence of folds or infolds of the conventional type heretofore described in which dust or bacteriological contaminants can collect is precluded, thus readily retain the sterilization characteristics of the packets.

The lesser volume of each of the packets also increases the length of time the packets will remain sterile owing to the compactness thereof.

The invention is further characterized in the provision of an envelope or wrapper into which the fibrous material packs, packets or elements are packaged, but only after being first formed in the manner heretofore noted. This advantageously prevents the conventional envelope infolding heretofore noted, and permits the covering or wrapping sheet to surround the packet in as fiat a form as that of the peripheral or boundary surfaces of the packet.

In accordance with the novel method of this invention it is also possible for the fibrous material to be first packaged in conventional envelopes, pressed to a desired shape, maintained under clamping pressure, cooled to at least room temperature, and then released. The packets formed in this way retain their precise configuration without tying and remain permanently in the pressed form. If desired, these packets may be then each inserted in an individual additional envelope or a plurality of such packets can be packaged in a single envelope. The packets may also be wrapped or packaged in the envelope after the pressing operation but before sterilization so long as the packets are immediately subjected to a clamping force after being packaged in the envelopes.

In accordance with the above the nature of this invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing.

Inthe drawing:

FIGURE 1 is a longitudinal sectional view of an apparatus constructed inaccordance with this invention, and it illustrates a container for exerting clamping pressure upon a plurality of packets therein during sterilization and cooling of the packets.

FIGURE 2 is a top plan view of the apparatus of FIG- URE 1, and more clearly illustrates the arrangement of the packets in the container.

FIGURE 3 is a side elevational view of another apparatus of this invention, and illustrates a plurality of packets subjected to the clamping pressure of a clamping device.

FIGURE 4 is a top plan view of the device of FIGURE 3, and more clearly illustrates the various components thereof.

A novel apparatus in accordance with this invention is illustrated in FIGURES 1 and 2 of the drawing, and

is generally designated by the reference numeral 1 (FIG- URE 1). The apparatus or device 1 is a container which includes a generally rectangular bottom Wall (unnumbered) and a plurality of outer walls 2 rising therefrom. The container is preferably open at its top and can be subdivided by one or a plurality of intermediate walls 3, only one of which is illustrated in FIGURES 1 and '2 of the drawing. The intermediate wall 3 can be positively secured to the container 1 or can be constructed for longitudinal adjustment in a conventional manner. The bottom wall (unnumbered) and the outer or side walls 2 of the container 1 are preferably of a solid construction, but can be provided with apertures (not shown).

A plurality of packs, packets or elements 4 formed from fibrous material of the type heretofore described in a conventional die cavity of a press are inserted one behind the other in the compartments (unnumbered) formed by the walls 2 and 3 of the container 1. The packets 4 areof a rectangular. configuration and are neither tied by conventional tying means nor inserted in envelopes. During the pressing operation the forces of the press acting against the fibrous material to form the rectangular packets 4 preferably acted'against the Wide sides of the packets, i.e., those sides parallel to the intermediate wall 3. Thus, when the packets 4 are positioned as shown in FIGURES 1 and 2 the wall 3 exerts between opposing walls of the container 1 and the packets 4 (or a single packet) can no longer expand beyond the volume produced by the pressure of the press.

The container 1 is of a height to accommodate both an upper row 5 and an adjoining row 6 of the packets 4 seated upon the bottom wall (unnumbered) of the container 1. Since the resilient or elastic nature of the fibrous material of the elements 4 in the rows 5 and 6 act in opposition to the direction of the press pressure, these 'rows 5 and 6 are similarly positioned with the wider surfaces or faces thereof in parallelism to the walls 2 and 3. Thus, the clamping forces of the opposing walls 2 and 3 of the container 1 are in thesame direction as the direction of pressure application in the press.

A plurality of packs 7 of fibrous material packets (unnumbered) are shown positioned in the right-hand endmost compartment of the container 1 as viewed in FIGURES 1 and 2 of the drawing. These packs 7 are formed by wrapping individual quantities of fibrous material in a sheet of paper or a similar covering and simultaneously subjecting the same to a pressing operation so that the entire group is pressed to a generally prismatic configuration. The group is then removed from the press and wrapped in a single sheet of wrapping paper or envelope as a single unit to form each of the packets 7 which are then inserted in the right endmost compartment of the container 1. The packs 7 are held under a predetermined clamping pressure in a manner substantially identical to that heretofore described in the consideration of the packets 4.

While the pressure is maintained by the container against both the packets 4 and the packs 7 therein the same are sterilized in a chamber, removed from the chamber and cooled to room temperature. Only after this cooling has occurred are the individual packets 4 or the packs 7 removed from the container 1, and upon such removal, both the packets 4 and the packs 7 retain their precise shape or configuration.

If desired, the clamping pressure exerted by the container 1 against the packets 4 and the packs 7 can be increased during both the sterilization and cooling steps by not only inserting as'many of these elements as will be readily accommodated therein in accordance with the multiple sizing of the container 1 heretofore to, but to adding one or two further ones of the packets 4 to slightly increase the clamping pressure exerted thereupon in the container 1.

Instead of a container, such as the container 1 of FIG- URES 1 and 2 of the drawing, a clamping device 8 (FIGURES 3 and 4) may be provided to clamp a pressshaped element, packet or pack, or a row or rows of such members during a sterilizing and cooling operation. The clamping device 8 includes a base plate 9 having a rigid upstanding wall 10 at a first end portion thereof and a longitudinally movable, adjustable wall 11 opposing the wall 10. The wall 11 is guided in a groove 12 formed in the base plate 9. Conventional securing means 13, such as a headed bolt riding in the groove 2 and a nut secured thereto, can be employed to secure the plate '11 in position to exert a clamping pressure on a stack of fibrous material packets '14 arranged between the plates 10 and 1d. The packets 14 are kept under the clamping pressure of the clamping device 8 during the sterilization and subsequent cooling of the packets 14 after which the same are released. Upon the release of the packets 14, the generally prismatic form thereof is retained permanently for the reasons heretofore discussed.

While examples of preferred apparatuses for and methods of forming packets of fibrous material are disclosed herein, it is to be understood that variations in the structure of the apparatus and the individual steps of the method may be made without departing from the spirit and scope of this invention as defined in the appended claims.

What I claim is:

1. A method of producing sterilized surgical packets of fibrous resilient reboundable material for dressing purposes comprising the steps of subjecting a predetermined quantity of fibrous material to a pressing operation to form a packed of predetermined configuration, exerting a clamping pressure against the packet to pre' vent the rebounding thereof and to maintain the pressed con-figuration of the packet, sterilizing the packet by application of heat, cooling the packet to room temperature, and thereafter removing the clamping pressure applied thereto.

2. The method of producing a packet as defined in claim 1 wherein the pressing forces and the clamping forces are applied from substantially the same direction against a packet.

3. A method of producing a sterilized surgical packet of "fibrous reboundable material for dressing purposes comprising the steps of subjecting a predetermined quantity of fibrous material to a pressing operation thereby imparting a particular configuration to the fibrous material, thereafter wrapping the contoured and pressed fibrous material in a covering, subjecting the wrapped and conformed fibrous material to a clamping pressure less than the pressing pressure but adequate to maintain the configuration of the conformed material, sterilizing the packet by application of heat, cooling the packet, and thereafter removing the clamping pressure from the packet.

4. A method of producing sterilized surgical packets of fibrous elastic reboundable material for dressing purposes comprising the steps of wrapping a quantity of fibrous material in a covering to form a shaped element, subjecting the shaped element to a pressing operation to form a shaped packet, thereafter subjecting the shaped packet to a clamping pressure for maintaining the configuration of the shaped packet, sterilizing the packet by application of heat, cooling the packet to at least ambient temperature, and only thereafter removing the clamping pressure from the packet.

5. A method of producing sterilized surgical packs of fibrous elastic reboundable material for dressing purposes comprising the steps of wrapping a quantity of fibrous material in each of a plurality of coverings, simultaneously subjecting the covered fibrous material to a pressing operation to form a plurality of wrapped packets, wrapping a plurality of the once wrapped packets in another wrapper to form a pack, subjecting the wrapped pack to a clamping pressure less than the pressure of the pressing operation to which the wrapped packets were subjected, sterilizing the packs by application of heat, cooling the packs to ambient temperature, and only thereafter removing the clamping pressure therefrom.

6. A surgical packet of fibrous reboundable material particularly adapted for dressing purposes consisting solely of a quantity of pressed, sterilized by application of heat and cooled reboundable fibrous material, said material being of a generally parallelopiped configuration and inherently retaining said configuration.

References Cited UNITED STATES PATENTS 1,108,539 8/1914 Zahm 21-2 1,661,140 2/1928 Nell et al. 21-2 3,084,424 4/ 1963 Engelking 2J6986 3,119,495 1/1964 Pratt 20663.2 3,148,771 9/ 1964 Miller 20'663.2

ADELE M. EAGER, Primary Examiner. 

3. A METHOD OF PRODUCING A STERILIZED SURGICAL PACKET OF FIBROUS REBOUNDABLE MATERIAL FOR DRESSING PURPOSES COMPRISING THE STEPS OF SUBJECTING A PREDETERMINED QUANTITY OF FIBROUS MATERIAL TO A PRESSING OPERATION THEREBY IMPARTING A PARTICULAR CONFIGURATION TO THE FIBROUS MATERIAL, THEREAFTER WRAPPING THE CONTOURED AND PRESSED FIBROUS MATERIAL IN A COVERING, SUBJECTING THE WRAPPED AND CONFORMED FIBROUS MATERIAL TO A CLAMPING PRESSURE LESS THAN THE PRESSING PRESSURE BUT ADEQUATE TO MAINTAIN THE CONFIGURATION OF THE CONFORMED MATERIAL, STERILIZING THE PACKET BY APPLICATION OF HEAT, COOLING THE PACKET, AND THEREAFTER REMOVING THE CLAMPING PRESSURE FROM THE PACKET. 